Re: Wrong statistics for size of XLOG_SWITCH during pg_waldump.

On 2021/03/19 18:27, Fujii Masao wrote:
>
>
> On 2021/03/19 15:06, Shinya11(dot)Kato(at)nttdata(dot)com wrote:
>>>>> But 0 value maybe looks strange, so in current version I show it like >below:
>>>>> Type N (%) Record size (%) FPI size (%) Combined size (%)
>>>>> ---- - --- ----------- --- -------- --- ------------- --- ...
>>>>> XLOG/SWITCH_JUNK - ( -) 11006248 ( 72.26) - ( -) 11006248 ( 65.78)
>>>>> Transaction/COMMIT 10 ( 0.03) 340 ( 0.00) 0 ( 0.00) 340 ( 0.00)
>>>>
>>>> I just wanted to know why the "count" and "fpi_len" fields 0 are.
>>>> So, it would be nice to have 0 values. Sorry for confusing you.
>>>
>>> Kato, it's not clear to me if you were asking for - to be changed back to 0?
>>>
>>> You marked the patch as Ready for Committer so I assume not, but it would be
>>> better to say clearly that you think this patch is ready for a committer to look at.
>>
>> Yes, I don't think it needs to be changed back to 0.
>> I think this patch is ready for a committer to look at.
>
> What's the use case of this feature? I read through this thread briefly,
> but I'm still not sure how useful this feature is.
>
> Horiguchi-san reported one issue upthread; --stats=record shows
> two lines for Transaction/COMMIT record. Probably this should be
> fixed separately.
>
> Horiguchi-san,
> Do you have updated version of that bug-fix patch?
> Or you started another thread for that issue?

I confirmed that only XACT records need to be processed differently.
So the patch that Horiguchi-san posted upthread looks good and enough
to me. I added a bit more detail information into the comment in the patch.
Attached is the updated version of the patch. Since this issue looks like
a bug, I'm thinking to back-patch that. Thought?

Barring any objection, I will commit this.

Regards,

--
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION